#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main() {
    int a = 0, b = 0, c = 0;
    while (~scanf("%d %d %d", &a, &b, &c))
    {
        if ((a + b) > c && (a + c) > b && (b + c) > a)
        {
            if (a == b && a == c && c == b)
            {
                printf("Equilateral triangle!\n");
            }
            else if ((a == b && a != c) || (b == c && b != a) || (a == c && c != b))
            {
                printf("Isosceles triangle!\n");
            }
            else
            {
                printf("Ordinary triangle!\n");
            }

        }
        else {
            printf("Not a triangle!\n");
        }
    }
    return 0;
}